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Double not (!!) operator in PHP
...ings or empty arrays) you will get the boolean value FALSE.
It is functionally equivalent to a cast to boolean:
return (bool)$row;
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Dispelling the UIImage imageNamed: FUD
...ister thread on the Apple Dev Forums received some better traffic. Specifically Rincewind added some authority.
There are issues in iPhone OS 2.x where the imageNamed: cache would not be cleared, even after a memory warning. At the same time +imageNamed: has gotten a lot of use not for the cache, b...
What does jQuery.fn mean?
...roperty.
The jQuery identifier (or $) is just a constructor function, and all instances created with it, inherit from the constructor's prototype.
A simple constructor function:
function Test() {
this.a = 'a';
}
Test.prototype.b = 'b';
var test = new Test();
test.a; // "a", own property
test....
SQL Server SELECT into existing table
... It is a best practice to always specify the columns no matter if they are all there or not. It will help prevent things from breaking when someone adds a column.
– HLGEM
Apr 24 '13 at 15:49
...
Which is better, number(x) or parseFloat(x)?
..., I find Number to be more reasonable, so I almost always use Number personally (and you'll find that a lot of the internal JavaScript functions use Number as well). If someone types '1x' I prefer to show an error rather than treat it as if they had typed '1'. The only time I really make an exceptio...
Reading a huge .csv file
...
You are reading all rows into a list, then processing that list. Don't do that.
Process your rows as you produce them. If you need to filter the data first, use a generator function:
import csv
def getstuff(filename, criterion):
with ...
Super-simple example of C# observer/observable with delegates
...
The observer pattern is usually implemented with events.
Here's an example:
using System;
class Observable
{
public event EventHandler SomethingHappened;
public void DoSomething() =>
SomethingHappened?.Invoke(this, EventArgs.Empt...
Is there a way to make mv create the directory to be moved to if it doesn't exist?
...ectories don't exist, is there some way to have those directories automatically created, so that you would only have to type
...
Maven command to list lifecycle phases along with bound goals?
...n wrong, but this command is the "reverse lookup" to the question (Listing all phases this goal is in)? link says "Displays a list of the attributes for a Maven Plugin and/or goals (aka Mojo - Maven plain Old Java Object)."
– user2039709
Nov 17 '16 at 13:45
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M_PI works with math.h but not with cmath in Visual Studio
...) and suddenly it compile perfectly.
Try moving it higher up the page. Totally unsure as to why this would cause issues though.
Edit: Figured it out. The #include <math.h> occurs within cmath's header guards. This means that something higher up the list of #includes is including cmath with...